Photonics Dictionary: A

The value of the distance of distinct vision, minimum focusing distance or near point, divided by the focal length of the lens. Magnification is produced when the optic is placed at its focal...

Stimulating light used for the production of energy through photosynthesis, solar cell or other light senstitive device.

That point in the electromagnetic spectrum at which an optical system focuses the most chemically effective rays.

Glass designed to absorb most infrared and ultraviolet radiation while transmitting most of the visible region.

Electromagnetic energy that is capable of producing photochemical activity.

Any of a series of radioactive elements with atomic numbers ranging from 89 to 103.

The creation of a chemical reaction in a substance when radiation is directed to it.

Agri-photonics refers to the application of photonics technologies in agriculture. Photonics involves the generation, manipulation, and detection of light and other forms of radiant energy whose...

A cathode-ray tube having a screen that is coated on the back with a thin film of aluminum, which serves to intensify the propagation of light.

The process of applying a film of aluminum to a surface, usually by evaporation in a vacuum.

Charged frozen pellets that are rapidly bombarded with a focused high-power laser to form a dense plasma that can be heated and sustained with neutral beams.

A visual defect that produces a disparity in the sizes of the images formed by the two eyes.

A light source that emits an uneven distribution of radiant energy through the visible range.

Anisotropic is a term used to describe a material or substance that exhibits different properties or behaviors in different directions. In other words, the physical or mechanical characteristics of...

Anisotropy refers to the property of exhibiting different values or characteristics when measured in different directions. In various fields, including physics, materials science, and geology,...

Gamma ray radiation released when matter and antimatter, such as electron and positron, unite and eliminate each other, transforming completely into energy. The resulting gamma ray spectrum depends...

The plot that expresses a reaction rate vs. the reciprocal of absolute temperature. Often used to describe the thermal characteristics of laser applications such as ablation or annealing.

A dark red opaque material that is transparent to the infrared beyond 1 µm.

The unit generally used to express distances within the solar system, and sometimes to measure interstellar distances. Technically, one astronomical unit is the mean distance between the Earth and...

Attosecond photonics sources refer to devices or systems that generate extremely short pulses of light on the order of attoseconds (1 attosecond = 10-18 seconds). These ultrafast light pulses are in...

Azadioxatriangulenium is a type of organic compound with a unique triangular molecular structure. It is often abbreviated as ADOTA. This compound belongs to the class of polycyclic aromatic...

An optical device, such as a Nicol prism, capable of producing plane-polarized light, and used for detecting the effect of the object on plane-polarized light produced by the polarizer.

The ability of a machine to perform certain complex functions normally associated with human intelligence, such as judgment, pattern recognition, understanding, learning, planning, and problem...

Image of a uniform source through the sample of a microscope image system. Light from the sample plane is reimaged by the objective into the image plane.

A form of roof prism used to invert an image. The prism has faces cut normal to the optical axis; therefore, the prism may be placed within the optical path of a system and invert the image without...

Device which measures the index of refraction of glass as well as the dispersion over visible range.

A reflecting prism that inverts the image. The image is reflected four times internally and emitted laterally. The prism is cut normal to the optical axis while the image is internally reflected from...

Designed for the function of optical wavefront analysis. Shack-Hartmann camera aberration sensors use a lens array to image the wavefront to the CCD image plane. Live feedback may be applied through...

The minimum energy required to induce atomic and molecular separation or displacement due to incident intense laser irradiation.

Ablation applied to polymers and chemical solids. Process of material removal that minimizes edge damage but will not heat the surrounding portion of the sample.

A high-brightness, short-duration source in which low-pressure gas initiates the discharge to vaporize material from the tube wall, leading to a high-pressure discharge of ionized wall material.

Optical surface damage due to abrasive rubbing. Abrasion damage affects are less than the thickness of the optical coating layers. Surface investigation may be achieved by aluminization of the coated...

Powder used to produce a smooth optical surface through abrasive polishing. Compounds may produce a surface finish specified for each.

The minimum value of luminance for vision. The value may vary with age as well as dark adaption period. (Measured range approximately log luminance -3 through 2.) About 10 -2 ml at the fovea, 10 -5...

Least value of color value combinations which gives white light; minimum purity as determined to be white.

The transition cross section constant coefficient which defines the transition probability of absorption from ground to a higher level within a given atomic or molecular species. The transition...

A hologram formed when the light of the illuminating beam is absorbed in correspondence with the recording exposure. In application, absorption holograms are intended for use in satellite...

The absorption index represents the imaginary component of the complex index of refraction, and not the real component. The imaginary component may characterize the attenuation per unit length...

An absorption peak refers to a sharp increase or spike in the absorption of electromagnetic radiation at a particular wavelength or energy level. It is a distinctive feature in the absorption...

An accelerometer is a sensor or transducer that measures the rate of change of velocity of an object, or in simpler terms, it measures acceleration. Accelerometers are widely used in various...

The range of angle or solid angle values by which light may enter an optical system.

Mount attached to a camera or camcorder which allows the user to attach a microphone or flash unit.

A broadband continuum resonator that confines a wide range of wavelengths. From the optical confinement a single wavelength may be released by means of a tuning grating.

Optic surface cleaning liquid that may be applied to glass, crystal, dielectric and metal surfaces; however, may not be applied to plastic and polymer materials.

An achromat, in the context of optics, refers to a type of lens or lens system designed to reduce chromatic aberration. Chromatic aberration is an optical phenomenon where different colors of light...